mongoimport -d test -c user_coll /var/www/aizhike/aizhike_DB/user_coll.json 
mongoimport -d test -c strategy_coll /var/www/aizhike/aizhike_DB/strategy_coll.json 
mongoimport -d test -c comment_coll /var/www/aizhike/aizhike_DB/comment_coll.json 
mongoimport -d test -c subscribe_coll /var/www/aizhike/aizhike_DB/subscribe_coll.json
